Fixed permission issues on client

client/allocdir/alloc_dir.go

@@ -313,13 +313,12 @@ func (d *AllocDir) Embed(task string, entries map[string]string) error {
 
 		// Embedding a single file
 		if !s.IsDir() {
-			destDir := filepath.Join(taskdir, filepath.Dir(dest))
-			if err := os.MkdirAll(destDir, s.Mode().Perm()); err != nil {
-				return fmt.Errorf("Couldn't create destination directory %v: %v", destDir, err)
+			if err := d.createDir(taskdir, filepath.Dir(dest)); err != nil {
+				return fmt.Errorf("Couldn't create destination directory %v: %v", dest, err)
 			}
 
 			// Copy the file.
-			taskEntry := filepath.Join(destDir, filepath.Base(dest))
+			taskEntry := filepath.Join(taskdir, dest)
 			if err := d.linkOrCopy(source, taskEntry, s.Mode().Perm()); err != nil {
 				return err
 			}
@@ -329,7 +328,8 @@ func (d *AllocDir) Embed(task string, entries map[string]string) error {
 
 		// Create destination directory.
 		destDir := filepath.Join(taskdir, dest)
-		if err := os.MkdirAll(destDir, s.Mode().Perm()); err != nil {
+
+		if err := d.createDir(taskdir, dest); err != nil {
 			return fmt.Errorf("Couldn't create destination directory %v: %v", destDir, err)
 		}
 
@@ -565,3 +565,67 @@ func (d *AllocDir) GetSecretDir(task string) (string, error) {
 		return filepath.Join(t, TaskSecrets), nil
 	}
 }
+
+// createDir creates a directory structure inside the basepath. This functions
+// preserves the permissions of each of the subdirectories in the relative path
+// by looking up the permissions in the host.
+func (d *AllocDir) createDir(basePath, relPath string) error {
+	filePerms, err := d.splitPath(relPath)
+	if err != nil {
+		return err
+	}
+
+	// We are going backwards since we create the root of the directory first
+	// and then create the entire nested structure.
+	for i := len(filePerms) - 1; i >= 0; i-- {
+		fi := filePerms[i]
+		destDir := filepath.Join(basePath, fi.Name)
+		if err := os.MkdirAll(destDir, fi.Perm); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// fileInfo holds the path and the permissions of a file
+type fileInfo struct {
+	Name string
+	Perm os.FileMode
+}
+
+// splitPath stats each subdirectory of a path. The first element of the array
+// is the file passed to this method, and the last element is the root of the
+// path.
+func (d *AllocDir) splitPath(path string) ([]fileInfo, error) {
+	var mode os.FileMode
+	i, err := os.Stat(path)
+
+	// If the path is not present in the host then we respond with the most
+	// flexible permission.
+	if err != nil {
+		mode = os.ModePerm
+	} else {
+		mode = i.Mode()
+	}
+	var dirs []fileInfo
+	dirs = append(dirs, fileInfo{Name: path, Perm: mode})
+	currentDir := path
+	for {
+		dir := filepath.Dir(filepath.Clean(currentDir))
+		if dir == currentDir {
+			break
+		}
+
+		// We try to find the permission of the file in the host. If the path is not
+		// present in the host then we respond with the most flexible permission.
+		i, err = os.Stat(dir)
+		if err != nil {
+			mode = os.ModePerm
+		} else {
+			mode = i.Mode()
+		}
+		dirs = append(dirs, fileInfo{Name: dir, Perm: mode})
+		currentDir = dir
+	}
+	return dirs, nil
+}

client/allocdir/alloc_dir_test.go

@@ -5,6 +5,7 @@ import (
 	"bytes"
 	"io"
 	"io/ioutil"
+	"log"
 	"os"
 	"path/filepath"
 	"reflect"
@@ -417,3 +418,67 @@ func TestAllocDir_ReadAt_SecretDir(t *testing.T) {
 		t.Fatalf("ReadAt of secret file didn't error: %v", err)
 	}
 }
+
+func TestAllocDir_SplitPath(t *testing.T) {
+	dir, err := ioutil.TempDir("/tmp", "tmpdirtest")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer os.RemoveAll(dir)
+
+	dest := filepath.Join(dir, "/foo/bar/baz")
+	if err := os.MkdirAll(dest, os.ModePerm); err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	d := NewAllocDir(dir)
+	defer d.Destroy()
+
+	info, err := d.splitPath(dest)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+	if len(info) != 6 {
+		t.Fatalf("expected: %v, actual: %v", 6, len(info))
+	}
+}
+
+func TestAllocDir_CreateDir(t *testing.T) {
+	dir, err := ioutil.TempDir("/tmp", "tmpdirtest")
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	// create a subdir and a file
+	subdir := filepath.Join(dir, "subdir")
+	if err := os.MkdirAll(subdir, 0760); err != nil {
+		t.Fatalf("err: %v", err)
+	}
+	subdirMode, err := os.Stat(subdir)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	// Create the above hierarchy under another destination
+	dir1, err := ioutil.TempDir("/tmp", "tempdirdest")
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	d := NewAllocDir(dir)
+	defer d.Destroy()
+
+	if err := d.createDir(dir1, subdir); err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	// Ensure that the subdir had the right perm
+	fi, err := os.Stat(filepath.Join(dir1, dir, "subdir"))
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+	if fi.Mode() != subdirMode.Mode() {
+		t.Fatalf("wrong file mode: %v, expected: %v", fi.Mode(), subdirMode.Mode())
+	}
+}